It has been suggested the former Magpies coach quit with The Magpies last month as he was already being lined up to replace George Burley at St Mary's.
However, Pearson has stated he only spoke to The Saints once his exit from Newcastle was finalised and that he was not even necessarily on the look-out for a managerial position.
"I want to put the record straight - when I left it was not for another job because I didn't have one," explained Pearson in the Daily Star on Sunday.
"I wasn't necessarily looking for a manager's job either. Kevin and people at Newcastle quite possibly felt I had left because I had a job lined up, but that was not the case.
"The fact of the matter is that the phone started ringing as soon as it was known I had left Newcastle and one of those calls was from Southampton.
"I drove straight down to talk to them that day. They gave me a great opportunity, even though I knew I was going into a relegation battle.
"I was surprised to be back in the game so quickly."